Cognitive problems can occur in the later stages of Parkinson’s disease, such as thinking difficulties and impaired reasoning. Emotional changes are also common, namely depression and anxiety. In fact, nearly half of sufferers experience clinical depression at some point in their lives, and it’s quite common for people living with chronic conditions to feel anxious. Dementia is another complication of Parkinson’s disease, due to abnormal protein deposits in the brain known as Lewy bodies. This causes memory loss, trouble concentrating, poor judgement, hallucinations, delusions, irritability, sleep disturbances, and anxiety. Some of these symptoms can be treated with the same medications that treat Alzheimer’s disease and other forms of dementia.
Sleep problems and disorders are a common complication of Parkinson’s disease. These issues range from trouble falling asleep and confusion at night, to acting out dreams and restless legs syndrome, to sleep apnea and frequent need to urinate. Additional bladder and bowel problems include stool leakage, diarrhea and constipation, constant urge to urinate, weak urine stream, and leaking with laughter, exercise, or sneezing. Most of these bladder and bowel issues can be resolved through lifestyle changes, like taking stool softeners, increasing intake of fiber and fluid, and going to the bathroom at regular times throughout the day.
A reduced sense of smell together with troubles eating can both occur with Parkinson’s disease. An impaired sense of smell is likely due to nerve damage from an abnormal buildup of a protein in the parts of the brain that are responsible for smell. As for eating, because Parkinson’s disease weakens the muscles in the mouth and the jaw, many long-term sufferers will find that they have problems swallowing and chewing. Trouble swallowing can lead to choking, which can then lead to pneumonia, as food and liquids leak into the lungs. Another eating-related issue is the production of too little or too much saliva, which can lead to uncomfortable swallowing and drooling, respectively.
Involuntary movements, otherwise known as dyskinesia, is a complication caused by the medication used to treat Parkinson’s disease, rather than a complication caused by the disease itself. More specifically, high doses of the drug levodopa can lead to head shaking, twitching, swaying, and fidgeting. These uncontrolled movements are a result of shifting dopamine levels in the brain. In other words, dopamine levels rise with levodopa, and drop as the drug wears off.
Similar to shifting dopamine levels, swings in blood pressure can also bring about a number of symptoms that affect approximately 20 percent of sufferers. For example, orthostatic or postural hypotension refers to dizziness upon standing from a seated or lying position, due to the drop in blood pressure that occurs when changing positions. In order to avoid these sudden drops in blood pressure, move slowly, drink extra fluid, and adjust the dose of certain medications.